One of my favorite things about kindergarten was hearing kids talk about Santa Clause. Some thought he wasn't real. Others were certain of his authenticity. Hearing them try to convince each other showed great thought in persuasion and faith in their own views.
I remember when our oldest son (about age 5 or 6) had a serious conversation with his dad about Santa Claus. Ben's Dad explained that seeing the joy on each child's face was so wondrful that parent's sgould get to share in the enjoyment. So parent's help Santa on Christmas Eve. He also pointed out that he could see that joy if he didn't tell his younger sisters.
About this time I overheard a discouraged young mother in the halls at church. She said dejectedly to an older, more experienced mother, "I'm a failure as a mother. All my preschool son thinks about is what he is getting for Christmas. He doesn't even think about giving." The more experienced mother said something I'll always remember. She said, "Don't you think one must experience the magic of what he is getting for Christmas first? Then he can imagine the joy someone else feels when they receive a gift."